Electrical Engineering Projects.

LulzBot Mini Research and Development

The LulzBot Mini has recently (November 15, 2016) had a huge overhaul with the introduction of Mini v1.04 (codenamed Gladiola). The changes made needed to be subtle enough whereas a SKU change did not have to be made, making the improvements even more challenging to pull off.

The requirements for the electrical system in this release were the following:

Use completely new and custom cabling which can handle continuous flexing and outlast the printers’ lifetime (praised by users)

Use the latest revision of Ultimachine’s Mini-RAMBo (with more unintentional radiating antennas)

The EMC improvements made could only be done at the machine/wiring level due to the electronics having been designed in proprietary software. Several Gladiola machines were tested and passed Class B, significantly increasing our sample size. Without proper grounding, shielding, and filtering the PCB could produce quasi-peaks which are as much as 10dB above the Class A limit. The radiated emissions were also found to be lower than several competitors.

Figure 1: Electronics enclosure before (v1.03 and earlier) and after (v1.04)